Lehman was responding to stinging criticism after his team crumpled to an innings and 78-run defeat inside three days in the fourth Test at Trent Bridge to give England a winning 3-1 lead in a series marked by disastrous Australian batting collapses.
While promising a "full and frank" review, Lehman said he retained great confidence in the future of Australian cricket, the coaching staff, his players and in the young players coming through.
Clarke's influence on the team's culture has been criticised by some former players since he announced he will retire after the fifth Test at the Oval next week. Lehmann sought an end to it.
"Michael deserves the chance to go out with the respect and dignity that he has undoubtedly earned over a fantastic career, and I want to see that career suitably celebrated," he said.
He said Clarke had been urged to miss this week's tour match against Northamptonshire.
"As a coach and as a selection panel, we know how much pressure and scrutiny comes with the job of captaining Australia's Test team and we want him to enjoy some time with his family who have come over to see him play his final Test," he said.
"It's similar to the approach we took with a number of players after the Lord's Test, when we thought a break was the best possible preparation for them."
He said the team could not be faulted for effort in preparation and training on tour.
"Even on the occasions when we've lost Test matches in three days, I don't see the value of scheduling extra training sessions.
"I can assure you the guys have trained as well as I've seen during the course of this tour but we just haven't been able to show that under the pressure of a game and I believe that flogging them with extra training day in, day out would just have a detrimental effect."
He took strong issue with criticism about WAGS accompanying the tour being a possible distraction.
"As a group, we have always placed a huge importance on family and while we're happy to cop criticism for the way we bat, bowl, field or prepare I believe it's unfair to suggest having families with us as a reason for our on-field efforts," he said.
"Some of the guys in our squad have schedules that have meant they've been at home for a total of three or four days since the Boxing Day Test last December - less than a week in more than seven months.
"This tour, with the Tests in the Caribbean prior to the Ashes and the limited-overs series that begins immediately after the current Tests finish, totals four months.
"There is no way, as coach of the Australian cricket team, that I am going to oversee a set-up that doesn't welcome wives, girlfriends, children and other family members when our players and staff are spending that length of time travelling.
"I find it strange that this has only surfaced as an issue now when it's been like this for the two years that I've been coach.
"In fact, wives, girlfriends and children have been part of Australia cricket team tours since Mark Taylor was captain 20 years ago and that is NOT going to change."
