WASHINGTON -- His words were halting, his body trembling, but Sen. Robert C. Byrd's message was unmistakable.
Seated in a wheelchair, the 92-year-old senator made his final committee appearance May 20 for a hearing featuring testimony from the controversial leader of Massey Energy, the owner of the Upper Big Branch coal mine where 29 of Mr. Byrd's constituents died April 5 in an explosion.
His voice rising, Mr. Byrd rattled off a list of safety violations and injuries at Massey mines for the company's CEO, Don Blankenship.
"This is clear as a noonday sun in the cloudless sky every day at Massey mines," Mr. Byrd said. "This is a clear, blatant disregard for the welfare and the safety of Massey miners. Shame! Do you care to comment?"
Often brash and defiant, Mr. Blankenship that day responded in measured tones that "we take violations extremely seriously," but the tongue-lashing he received from the longest-serving member of Congress in history was the hearing's defining moment.
That it was one of the final official acts for Mr. Byrd, who died last Monday and will be buried Tuesday, was reflective of the senator's evolving, more aggressive stands against the coal industry in recent months.
Coal -- particularly in Mr. Byrd's native southern West Virginia -- is viewed as a vital engine to the economy of a state where industry leaders hold significant political sway. They did not view Mr. Byrd as hostile to the industry through his career, but he raised eyebrows in the past year by backing strict environmental regulation of mountaintop removal mining, a controversial practice in which the tops are taken off mountains to expose the coal underneath.
In an essay and accompanying radio address in December entitled "Coal must embrace the future," Mr. Byrd took a sharper tone than he had in the past.
"We have our work cut out for us in finding a prudent and profitable middle ground -- but we will not reach it by using fear mongering, grandstanding and outrage as a strategy," Mr. Byrd said.
"As your United States senator, I must represent the opinions and the best interests of the entire Mountain State, not just those of coal operators and southern coalfield residents who may be strident supporters of mountaintop removal mining."
Because of his stature and considerable clout, industry leaders did not dare to utter a critical word in response, but his words did cause a stir.
"We had some concerns with some of his most recent actions," said Chris Hamilton, senior vice president of the West Virginia Coal Association. "It's my belief that he felt in order to preserve his leadership position that he had to moderate his positions, at least to the outside world."
To leaders of the environmental lobby, however, "It was such a breath of fresh air," said Don Garvin, legislative coordinator for the West Virginia Environmental Council.
Mr. Byrd also became more supportive of climate legislation. In one of his final votes last month, he broke from fellow West Virginia Democrat Jay Rockefeller to vote against a resolution to block the federal Environmental Protection Agency from regulating greenhouse gases.
"To deny the mounting science of climate change is to stick our heads in the sand and say 'deal me out' of the future," Mr. Byrd said in a statement that day.
It was quite a reversal for a politician who led the charge against the 1990 Clean Air Act.
West Virginia political science professor Susan Hunter said Mr. Byrd's longevity and popularity gave him an almost unique ability to be above the influence of the coal industry.
"You tend to think of politicians of always going where the money is," Dr. Hunter said. "Robert Byrd didn't have to depend on big business giving him a lot of money to stay in office. So he could take positions and think about whether mountaintop removal was a good choice or not."
Mr. Byrd's positions, Dr. Hunter said, were rooted in what he felt was best for West Virginia's working class, and he always referenced his own humble beginnings. In Mr. Byrd's later years, he came to believe that the effective way to help working West Virginians would be to urge diversification into alternative energy technologies and to protect those who are harmed by environmentally insensitive mining practices.
"He was an adamant protector of coal jobs, and I think until he died he was an adamant protector of West Virginia jobs," Dr. Hunter said. "But he was also a very smart man, and I think he began to realize that there were other ways West Virginia could move and keep jobs."
His fight for the working class extended to mine safety.
Mr. Byrd was particularly active in drafting the landmark MINER Act in 2006 after 19 workers died at the Sago and Aracoma mines in West Virginia and the Darby Mine in Kentucky. He also was quick to excoriate Massey Energy after the Upper Big Branch explosion.
"I'm not sure he didn't allow some personal issues to come into play during the sparring with the Massey CEO at that hearing," said Mr. Hamilton of the West Virginia Coal Association, taking care to parse his words. "But, nonetheless, I think his motives and underlying desire to see mine safety improve was at the base of his remarks and thoughts."
Mr. Byrd's replacement will be appointed by Gov. Joe Manchin, who said he will not consider a successor until after Mr. Byrd is buried Tuesday.
A Democrat who is expected to run for the seat himself in 2012, Mr. Manchin is viewed by environmentalists as having closer ties to the coal industry, and he has been critical of the federal government's actions on mountaintop removal and climate change.
"I hope it's someone who is for the most part green," Mr. Garvin, of the West Virginia Environmental Council, said of the state's next senator.
"But I fully expect it to be someone who will take up Manchin's positions on climate change and mountaintop removal mining in West Virginia."
Daniel Malloy: email@example.com or 1-202-445-9980. Follow him on Twitter at PG_in_DC.