May 5 (Reuters) - The following are the top stories from selected Canadian newspapers. Reuters has not verified these stories and does not vouch for their accuracy.
** Ontario's prisons adviser has laid out a plan that would catapult the province's prison system from a national laggard to one of the most progressive in the world by placing hard limits on the use of solitary confinement and prohibiting the segregation of vulnerable prisoner populations. tgam.ca/2pd0R0W
** Ontario Premier Kathleen Wynne's cabinet is prepared to unleash a Buy Canadian-style policy to turn the tables on any U.S. state that adopts Buy American provisions despite the province's aggressive lobbying. tgam.ca/2pd0Vhc
** California legislators are proposing sweeping changes to the U.S. state's cap-and-trade program that could raise the costs of greenhouse-gas emission reductions in Ontario and Quebec. tgam.ca/2pcS0fO
** Michael Medline, the former Canadian Tire chief executive hired in January to help turn around Empire Co , announced a three-year transformation plan Thursday aimed at saving the owner of Sobeys and Safeway C$500 million a year by the end of fiscal 2020. bit.ly/2pcSbaW
** The Canadian Imperial Bank of Commerce has sweetened its bid to acquire Chicago-based PrivateBancorp Inc for the second time, adding an additional $3 in cash for each share of common stock held. bit.ly/2pdaw7P
** Montreal-based SNC-Lavalin Group Inc reiterated diversification plans at its annual shareholder meeting Thursday, while also repeating calls for a delayed prosecution agreement to help it secure major overseas contracts. bit.ly/2pcU9YY (Compiled by Vishal Sridhar)