Players who don't attend minicamp are subject to fines, but Belichick said Waters, the team's starting right guard in 2011, is "excused for personal reasons."
Speculation about Waters' future began after Super Bowl XLVI, when Waters said immediately after the game that he'd consider retirement. A source close to the 35-year-old Waters later said that he planned to play, although that was months ago.
Waters, who played for the Chiefs from 2000-2010, has traditionally spent the offseason at home in Texas with his family. Last year, he joined the Patriots after training camp as a free agent.
Asked if Waters has given the Patriots any indication of his plans to play in 2012, Belichick said he didn't have anything to add.
"He obviously had a great year. He played a lot. He played well," he said of Waters' 2011 season during which he started all 16 games.
Asked if he sees Waters being able to maintain a high level of performance this year, Belichick said, "I don't know. I think any time players get closer to the end of their career, whatever that is, you evaluate them on a year-by-year basis. Some players are improving in their early 20s, the early part of their career, and then there is some point in their career ... nobody is going to play forever. I don't think he is any different than anybody else."
With Waters not in town, and having not participated in voluntary work, it creates a new wrinkle in evaluating where Waters is at this point.
"It's an opportunity for the guys that are out there," Belichick said.