If stock markets are any indicator, oil and gas investors are cheering Prime Minister Justin Trudeau’s decision to step down as Liberal leader.Minutes after Monday's announcement, the Toronto Stock Exchange’s capped energy index was up nearly two percent despite a decline for the broader market and a drop in oil prices.Calgary-based Canadian Natural Resources jumped 62 cents or 1.3% to $46.23 while Suncor Energy gained 31 cents to $52.95.Tourmaline Oil Corp. was one of the leading performers on the day, adding $2.37 or nearly 4% to hit $69.15, just off a 52-week high of $69.50..It comes amid hopes a change in leadership will delay or result in the outright cancellation of a series of policies aimed squarely at the oil and gas sector, including a proposed emissions cap Alberta’s UCP government says amounts to a de facto production cut of at least 1 million barrels per day (bpd) -- or nearly 20% of Alberta’s present output.“Today is a fantastic day for energy investors, and one that I’ve been praying for,” senior portfolio manager Eric Nuttal told BNN news. “Very clearly Justin Trudeau’s economic policies over the past nine or 10 years have been a total failure, specifically for energy. It would be impossible to ask for a more antagonistic prime minister.”Barring any new “whacko” energy policies, “today’s announcement, I think, is the beginning of the elimination of the energy risk discount being applied to our (oil and gas) stocks.”Nuttal said investor interest in energy companies remains high despite a litany of government laws like C-69, the ‘no more pipelines’ act and C-59, the ‘greenwashing’ law that stifles oil companies from touting environmental benefits of new production technologies.Although he thinks oil sands companies are uniquely poised to benefit from a change in government, Nuttal said the start-up of the major new liquified natural gas projects like the massive LNG Canada project on British Columbia’s West Coast heralds a longer secular growth cycle for Alberta producers.“Not just the outlook for oil… the outlook for natural gas is very, very strong.”